While actor Charlie Hunnam's star has been rising in recent years thanks to the success of such TV series as "Sons of Anarchy," "Undeclared" and "Queer as Folk," there's no question he's taking a big step to the next level with the lead role in "Pacific Rim," director Guillermo del Toro's hotly anticipated robots vs. monsters action fantasy.

Despite the pressures that come with such a monumental role, Hunnam, 33, has managed to remain on an even keel -- and is clearly very humbled by his rising stardom. Realizing that any number of things can affect the outcome of his work, Hunnam told me in a recent interview the best thing he can do is not be afraid of all the things that could potentially go wrong on a gig, but instead keep a positive focus on all the things that can go right -- starting with his own performance.

"As an actor, one always puts oneself out there, and there's always a fear that you are not going to do as good a job as you would hope to do because there's a million variables that can come into play and prevent you from doing that," Hunnam said. "I try to approach my career from a positive standpoint and just have as much confidence in my own abilities as possible. You can overcome fear with a lot of hard work and do a lot of research."

Plus, the British performer added, it's important to heed the advice of the people you admire most in the business.

"I always think back to Daniel Day-Lewis, who said why he does the massive amount of preparation and research that he does," Hunnam observed. "He said, 'I'm not a good enough actor not to do the research,' and that's how I feel. If I didn't show up and do a tremendous amount of work, then I would mess everything up. I suppose in a certain way, that is operating out of fear, but I also feel fear can be very, very destructive for an actor, because you do ultimately need to go into the part having the confidence that you've got what it takes to play it. Otherwise, you're just going to constantly be second-guessing yourself."

"Pacific Rim" follows the story of Raleigh Becket (Hunnam), a gifted co-pilot of a Jaeger -- a 25-story-tall robot vessel designed to fight the Kaiju -- a brutal race of monsters who rise up from underneath the sea to wreak havoc on humanity.

Devastated by a tragedy that resulted in deep, personal loss, Raleigh leaves the human resistance -- only to be coaxed back five years later because the Kaiju are posing a threat that could lead to the extinction of Earth's other inhabitants.

Also starring in a pivotal role in the film is del Toro's frequent collaborator, Ron Perlman, who has worked with Hunnam for the last five years on "Sons of Anarchy." In a separate interview, Perlman told me that Hunnam has definitely taken his craft to a whole new level on "Pacific Rim."

"Charlie carries this film; he's the heart and soul of this film," Perlman said. "I also had long conversations with Guillermo about him, and Guillermo is really happy with the level to which Charlie took his game on this thing. He's doing what he needs to do, and being the hero in a film of this scope is a very heavy lift. I think it's going to be a game-changer for Charlie, and it couldn't have happened to a nicer kid. He's a hard-working, very earnest and very sweet human being. "

Jaeger-timeFor "Pacific Rim," Hunnam found himself doing as much physical preparation for the role as mental, since Raleigh and Mako fight the Kaiju while operating the Jaeger in the head of the massive machine. That's because del Toro, who could have gone with a green-screen technique to film the scenes digitally, instead had chosen to build the set to scale -- which gave Hunnam and Kikuchi the workouts of their lives.

Hunnam loved the idea of physically working the contraptions del Toro had commissioned -- at first, anyway.

"I felt it was cool until I spent two or three days in it, when I said, 'Can we not just do this in CGI, people?'" Hunnam recalled, laughing. "But it's an amazing invention that Guillermo came up with."

Despite the physical rigors, Hunnam added, the outcome of not taking the shortcut of computer-generated imagery in that instance well worth it.

"It was a brutal process, actually, operating that thing. It was like being on an elliptical at high resistance for 14 hours a day, wearing a suit that weighed 30 pounds, while having 200 gallons of water a minute being poured on my head," Hunnam remembered. "It certainly was a challenging ordeal, but it looks wonderful in the movie."

Hunnam said seeing the completed film in its full glory not only opened his mind and inspired the wonder of science fiction one day becoming science fact, it made him believe the ultimate dream of world peace is something that could be realized.

"I think it is certainly conceivable that we can construct these machines, but hopefully we wouldn't construct them for war," Hunnam said. "I think what is so beautiful is about this movie -- and what people might be surprised by, maybe -- is that in its heart, it's just a really simple human story. That's what the film needs, because the concept of monsters fighting robots has no context without a human story."

And tucked within that human story, Hunnam added, are some valuable lessons.

"What Guillermo did was used the film as an allegory of what we're facing today," Hunnam said. "The message of the film is: Whether it's giant monsters or the world population exponentially rising or global warming or nuclear warfare -- all of the myriad of problems we face as human beings -- if we could just forget our petty differences and come together to figure out solutions, then we may have a future. If we don't, apocalypse is nigh.

"That's one of the things you can do with these giant stories, is tackle these huge themes in a way that you're not hammering the audience over the head," Hunnam added. "They're subtle, but those themes are not going to be lost on anybody."